chore(Grid): update breaking change article

Author: xristianstefanov

components/grid/grouping/load-on-demand.md

@@ -161,11 +161,11 @@ Scroll through the groups or expand them to load their data on demand
 
         if (args.Request.Groups.Count > 0)
         {
-            args.Data = result.GroupedData.Cast<object>().ToList();
+            args.Data = result.GroupedData;
         }
         else
         {
-            args.Data = result.CurrentPageData.Cast<object>().ToList();
+            args.Data = result.CurrentPageData;
         }
 
         args.Total = result.TotalItemCount;

upgrade/breaking-changes/7-0-0.md

@@ -43,6 +43,7 @@ The obsolete `ClearButton` parameter is removed. Use `ShowClearButton` instead.
 * The obsolete `AutoFitColumn()` method is removed. [Use `AutoFitColumnAsync()`]({%slug components/grid/columns/resize%}#autofit-columns) instead.
 * The obsolete `AutoFitColumns()` method is removed. Use `AutoFitColumnsAsync()` instead.
 * The obsolete `AutoFitAllColumns()` method is removed. Use `AutoFitAllColumnsAsync()` instead.
+* When using grouping and `OnRead`, casting the `DataSourceResult.Data` to a list of objects (`.Cast<object>().ToList();`) is no longer needed.
 
 ## TextArea